Implantable infusion systems are used to provide programmable long-term delivery of a therapeutic agent, e.g., infusate drug, to a target tissue location within, for example, the brain, spinal canal, or epidural space. These systems typically include a pump implanted at a remote location, e.g., within the abdominal or chest cavity, wherein the pump is connected to a catheter, the catheter having its distal end implanted at the target tissue location. In use, the therapeutic agent is delivered from a reservoir in the pump to the target tissue location via the catheter.
Some therapies, e.g., treatments of many neurological diseases, may benefit from infusion of a therapeutic agent to multiple locations within the body. For instance, for the treatment of Parkinson's disease, it may be beneficial to deliver a therapeutic agent, e.g., Glial Derived Neurotrophic Factor (GDNF), to both hemispheres of the brain (bilaterally). Infusing the therapeutic agent to such multiple target tissue locations can be accomplished by using multiple infusion systems, e.g., a separate pump and catheter with a single exit hole for each target tissue location. However, multiple systems result in not only increased costs and patient invasiveness (as compared to single target tissue location systems), but also increased complexity that is inherent in such multiple systems.